U–Pb zircon geochronology is hampered by problems acquiring meaningful geologic ages on zoned grains that retain isotope signatures from multiple growth or thermal events. We present a new method using laser ablation-multicollector-inductively coupled plasma-mass spectrometry to overcome complications asso­ ciated with intricately zoned zircon crystals through in situ sampling of zircon volumes...

Monazite in a granite pegmatite from Yamanoo, Sakuragawa, Ibaraki Prefecture, Japan has been examined terms of U, Th, Pb, and rare earth element (REE) chemistry by electron microprobe analysis. This occurs as lenticular vein the Kabasan granitic body. Oscillatory sector zoning were observed back-scattered images. An averaged empirical formula was (Ce0.286Nd0.180Sm0.104La0.077Y0.069Pr0.041Gd0.06...

Correction for 'Sequential separation of ultra-trace U, Th, Pb, and lanthanides using a simple automatic system' by Yutaka Miyamoto, et al., Analyst, 2015, DOI: 10.1039/c5an00027k.

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Meteoritic zircons are rare, but some are documented to occur in asteroidal meteorites, including those of the howardite–eucrite–diogenite (HED) achondrite clan (Rubin, A. [1997]. Meteorit. Planet. Sci. 32, 231– 247). The HEDs are widely considered to originate from the Asteroid 4 Vesta. Vesta and the other large main belt asteroids record an early bombardment history. To explore this record, w...

The isotopic composition of U in nature is generally assumed to be invariant. Here, we report variations of the U/U isotope ratio in natural samples (basalts, granites, seawater, corals, black shales, suboxic sediments, ferromanganese crusts/ nodules and BIFs) of 1.3‰, exceeding by far the analytical precision of our method ( 0.06‰, 2SD). U isotopes were analyzed with MC-ICP-MS using a mixed U–...

The aim of this study was to test a possible use of Urtica dioica (common nettle) plant as a biomonitor of polonium (210)Po and lead (210)Pb contamination near phosphogypsum stacks by determining concentrations of these radionuclides in samples collected from the area of phosphogypsum stockpile in Wiślinka (northern Poland). The (210)Po and (210)Pb contents in roots depended on their concentrat...

a r t i c l e i n f o Keywords: silica-undersaturated volcanism 238 U-230 Th-226 Ra-210 Pb series disequilibria magma transport and residence time carbonate metasomatism volcanic hazard assessment The silica-undersaturated Nyiragongo volcanics, located in the East African Rift, have globally unique chemical compositions and unusually low viscosities, only higher than carbonatite lavas, for terr...

The isotopic thermochronological study included the U–Pb (SHRIMP) and fission-track dating of zircon and fission-track and (U–Th)–He dating of apatite from syenite intrusions cropping out in the eastern slope of the Sredinnyi Range of Kamchatka. The emplacement time of the intrusion was determined, and its exhumation velocity was evaluated. According to U–Pb (SHRIMP) zircon dating, the age of s...